Answers

Protect from frost; damage below 40° F.
Needs lot of water but the soil should be well drained, rich and moist soil is needed as well, high humidity.
Plant in frost free spots or areas; can also be planted in the greenhouse.
Optimum temperature range is 60° - 78° F.
Psittacorum are, to some degree, winter hardy.

And then wait !!

or the other one Clianthus puniceus -- Sow March- May. Soak seeds in hand hot water for 24 hours. Then sow seed 6mm (¼in) deep into pots or trays. Keep in a warm place at a temperature of between 15-21C (60-70F). After sowing, do not exclude light as this helps germination. Keep the surface of the compost moist but not waterlogged; germination will usually take 14-30 days. When large enough to handle, transplant seedlings into 7.5cm (3in) pots or trays.